Milling attachment



March 31, 1936. HQFMANN 2,035,810

" MILLING ATTACHMENT Original-Filed June' 20, 3 7 Sheets-Sheet l as? l 155 l N V E N TO R Alfred flofmq/m ATTORNEYS March 31, 1936-. HQFMANN 2,U35,81@

MILLING ATTACHMENT Original Fil ed June 20, 1954 7 Sheets-Sheet 2 INVENTOR Alf yd Haimann I RNEYS March 31, 1936. A H N 2,935,81Q

MILLING ATTACHMENT ori inai Filed June-20, 1934 7 Sheets-Sheet 4 INVENTOR Alf'red Hui-man March 31, 1936. A. HOFMAIQN 2,035,8M

MILLING ATTACHMENT 7 Sheets-Sheet 5 INVENTOR TTO EYS Alfred f/ofmamn March 31 1936. HQF'MANN 2,035,810

MILLING ATTACHMENT Original Filed June-2 0, 1954 7 Sheets-Sheet 7 INVENTOR Alfred Half-man BY L0 "2% Patented Mar. 31, 1936 iii'i'E STATES PATENT OFFICE fred Hofmann Needle N. .L, a corporation of Works, Inc., Union City, New Jersey Original application June 20, 1934, Serial No. 731,440. Divided and this application June 22,

1935, Serial No. 27,839

6 Claims.

This invention is for improvements in milling machines of a type more particularly adapted to combination with other attachments to provide automatic metal working machines.

An object of this invention is to provide a milling head in several forms in which work pieces of varying diameters or contour may be milled.

Another object of this invention is to provide in a milling head movable supporting mechanism for the milling cutters and means for effecting movement thereof to cause the milling cutters to follow the contour of a work piece.

A further object of this invention is to provide in such an arrangement driving mechanism for effecting rotation of the milling cutters on their axes as they are moved to follow the contour of a work piece.

The inventions herein disclosed have many 20 specific objects, the nature of which and the manner of attainment will be apparent from the following detailed description when taken in connection with the attached drawings.

This invention resides substantially in the combination, construction, arrangement, relative location of parts, steps and series of steps, all as will be set forth in full detail in the following specification in connection with the attached drawings, and pointed out in the appended 30v claims.

This application is a division of my copending application Serial No. 731,440, filed June 20, 1934 for Method and machine for making knitting needles.

In the drawings,

Figure 1 is a cross sectional view taken on the line I-I of Figure 3 of one form of milling head in accordance with this invention;

Figure 2 is a cross sectional view taken on the line 2-2 of Figure 3;

Figure 3 is a cross sectional view taken on the line 3-3 of Figure 1;

Figure 4 is an elevational view of the beard end of a knitting needle representing one form of work piece which. may be operated upon by means of the milling attachments of this disclosure;

Figure 5 is a cross sectional view taken on the line 5-5 of Figure 7, showing a modified form of milling head in accordance with this invention;

Figure 6 is a cross sectional View taken on the line 6-5 of Figure 7;

' Figure '7 is a cross sectional view taken on the line 1-1 of Figure 5 Figure 8 is a vertical, central, longitudinal, cross sectional view through another form of milling attachment in accordance with this invention;

Figure 9 is a cross sectional view taken on the line 9-9 of Figure 8;

Figure 10 is a cross sectional view taken on the line III-I of Figure 9;

Figure 11 is a cross sectional view taken on the line II-II of Figure 8; and

Figure 12 is an elevational view illustrating the action of this milling attachment upon the sides of a knitting needle at the slot.

The milling heads or attachments comprising the invention herein disclosed form part of a larger combination comprising an automatic machine for manufacturing spring beard knitting needles from wire stock. For this reason the operation of the milling heads herein disclosed will be described in connection with spring beard needles as indicated in Figures 4 and 12, although it is of course apparent that these mechanisms may be employed for operation upon many other forms of work pieces. It will likewise be apparent that the structures herein disclosed may be used independently of other mechanism, and of each other, or may be used as parts of a larger combination such as that represented in the parent application above referred to.

The milling attachment which reduces the diameter at the end of the needle in preparation for swedging is illustrated in Figures 1 to 3 inclusive, and the form of the needle after the milling operation is shown in Figure 4. This attachment comprises a support I40 mounted on the table I, and formed into a housing I4I having a pivotally mounted cover I42 upon which is mounted an adjustable stop. A pair of beveled gears I44, driven from the power source, operate the shaft I45, and the upper meshing beveled gears I 46. One of these beveled gears is keyed to an enlarged shaft I41 journaled in the housing I4I.

Mounted around the large sleeve for the shaft I 41 is a circular plate I48 which has keyed thereto a gear I 50 which locks with a fixed gear I51 (see Figure 2) mounted on the housing I4I. These gears and plate are locked in the housing through the flange II of shaft I41. The plate I48 supports a fixed bevel gear I49. Mounted on the enlarged end I5I of shaft I41 are the brackets I52 in which are journaled the bevel gears I53, which mesh with the bevel gear I49. These bevel gears drive the pairs of gears I54, one of each of which is secured to the same shaft to which one of the bevel gears I53 is attached, and the other of which is secured to a shaft upon which the milling cutters I56 are mounted. The milling cutter shafts are journaled in the pivotally held brackets I55. Thus the milling cutters I56 are caused to re volve on their axes through the gear trains which in turn are driven by reason of the fact that the supporting mechanism therefor revolves with shaft I41. Thus the milling cutters as they cut rotate around the periphery of the wire, maintaining a circular cross section while reducing its diameter.

Pivotally mounted on brackets I55, as shown in Figure 2, are a pair of bell crank levers which have the arms I58 projecting into a recess in the shaft I41 and provided with springs for urging them towards each other. The other arm of these bell crank levers carries a set screw I52 to adjust the bell crank levers into proper relationship with the pivotally mounted brackets I55.

The purpose of journaling the milling cutters in the pivotally mounted brackets I55 in connection with the pivotally supported bell crank levers is so that they may be opened at the time the end of the wire is inserted between them, and may be closed for the milling operation when the wire is slowly removed from between them. The movement of the milling cutters from and towards the end of the wire is effected by means of the slidably mounted shaft I59, which has an inner conical end which passes between the arms I58 of the bell crank levers. Rod I59 is shown in Figure 3 at the left hand position, at which time it has forced the arms I58 apart against the action of the springs resting between them and the inner wall of the recess in shaft I41, thereby moving the milling cutters together. The action of moving the milling cutters towards each other does not occur instantaneously but is a progressive action determined by the slope of the conical end of the rod I59. In other words, as the milling action goes on, these cutters gradually move together until the end of the wire is reduced to the desired minimum diameter. The sliding movement of rod' I59 is effected through the pivotally mounted lever I60, which is operated by lever I6I through the link connection I62 and the bell crank lever I63, which in turn is given the proper movement by the cam I64. Thus, at the beginning of the operation the milling cutters I56 are wide open and the chuck assembly or work holder 4' projects the end of the wire between them. Cam I64 then begins to slowly move rod I59 to the left (Figure 3), gradually moving the milling cutters towards each other, until the rod I59 has moved in the full distance. In the meantime, of course, the cutters are rotated about the surface of the wire, giving it a circular cross section, while the chuck I I 4 slowly withdraws the wire.

The end of the wire is supported as shown in Figure 3 in a guidemounted on I52. The chuck assembly H4 is then'gradually withdrawn with the result that the wire is milled down at the end of its predetermined diameter. After the wire is fully withdrawn the main turret moves on and cam I64 continues its operation to withdraw arm I60, permitting the spring around the rod I59 to follow it as it moves to the right.

As indicated for example in Figure 3 the work piece may be presented to the milling head by a chuck or other suitable work holder which may or may not comprise part of an automatic feeding and holding mechanism. It is also positioned to manually present the work pieces to the milling head. It may be emphasized that the end of the work piece is reduced to. a desired uniform diameter of accurate circular cross section by reason of the fact that the milling cutters revolve about the axis of the work piece as they rotate on their own axes and as the work piece is slowly Withdrawn from between them. At the same time the milling cutters may be caused to move either towards or away from the work piece thereby modifying its contour, in accordance with the shifting of the cam end of the rod I59, as will be apparent to those skilled in the art.

A milling head of somewhat similar construction has been illustrated in Figures 5, 6 and '1, and will now be described in detail. This attachment comprises a fixed base I89 secured to the table I and provided with a housing I90. At I9I is a shaft driven from below the table from the power source, which in turn drives through the meshing bevel gears I92, the gear train I93, I94, and I95. Gear I93 is mounted on a fixed axis while the idler gear I94 and the gear I95 are rotatably mounted on the arm I91 which is pivotally mounted on the axis of gear I93. Gear I95 is attached to a. short shaft to which the milling cutter I96 is secured. This milling cutter is positioned over an anvil I91" (Figure '7), which is mounted in back of the guide piece I91, which has a conical opening for guiding the needle on to the anvil.

Here again, as illustrated in Figure 7, the work piece N is held in a chuck II4, which is operated to slowly withdraw the work piece from the attachment so that the milling cutter operates on the top surface of a portion thereof next adjacent to the reduced end as produced by the previously described structure. The purpose of the adjustable stop screw 2 is of no importance here, although it may be noted that it determines the distance which the chuck II4 inserts the work piece into the milling attachment when an automatically operated work holder is employed.

The lever the cutter so that the cutter is raised during the insertion of the needle and is then moved down so as to engage the top of the needle and to be gradually fed thereinto to get the proper depth of out. As soon as the milling cutter'has been moved into the work the proper distance as determined by cam 206 the work piece is then slowly withdrawn causing a continuation of the cut for any desired distance. It is of course apparent that the camming edge of the cam 206 may be modified as desired to continuously or intermittently vary the depth of the cut taken by the cutter. The movement of the milling cutter into contact with the needle is accomplished by means of a cam operated lever. The end of lever I91 is provided with an arm I98 which terminates in a pin I99 riding in the forked end 200 of the lever 20I. This lever is pivotally supported on a screw 202 which is mounted in a block 203 vertically adjustable by means of the screw 204 (Figure 5), so as to determine the range of movement of the milling cutter. Lever 20I is provided on its outer end with a roller 205 which engages an oscillatable cam 296 which is pivotally mounted on the hous- I 91' pivotally movable, supports ing'and secured to a shaft to which the lever is secured. Lever 231 is connected by a rod 238 to a pivotally supported bell crank lever 209 oscillated by a cam 2H! driven from the power source below the table. Thus after the needle is fully in and resting on the anvil I97" the cutter is fed into it as cam 203 moves upwardly, causing the forked end 200 of lever 20l to move downwardly (Figure '7). ment of lever 20! causes. lever I91 to move downwardly to the proper depth. The needle is then slowly withdrawn, milling a complete flat on the top thereof.

Here again the Work piece may be manually presented to the milling head if desired.

The third form of milling head is illustrated in Figures 8 to 12 inclusive. In this attachment continuing the description in connection with a knitting needle N, the sides of the slot N3 are milled to the proper dimensions.

This attachment mills the sides of the slot as indicated in Figure 12, as the needle is withdrawn from between the milling cutters 320 against direction of rotation.

The needle is inserted between the milling cutters when they are separated and when positioned the milling cutters move together to the full line position up to the extreme left hand end of the sides of the slot so that the straight portions of the side may be milled as the needle is withdrawn. When the needle is withdrawn to the point where the straight sides converge in to the needle point the milling cutters are given a further movement towards each other in the proper timed relation to the movement of the needle, so as to mill the converging sides of the slot. At the end of the operation the milling cutters have been moved to the position indicated by the dotted line circles in Figure 12.

This attachment (Figures 8, 9, 10, and 11) comprises a housing 301 secured to the table i, so that the chuck IM may present a needle thereto. Slidably mounted in the base of the housing is the operating member 308 for giving the milling cutters the proper movement towards and away from the needle. This member comprises a plurality of cylindrical sections connected by the conical portions 308 and 308". The member 308 is given sliding movement by means of the link 309 pivotally connected to the lever Bill which is secured to the same shaft to which the lever 3 is secured. Lever 3!! is pivotally connected by means of the link rod 3l2 to a pivotally supported lever 3I3 which is oscillated by the cam 3M supported below the table and operated from the power source in the proper timed relation, as will be clear to those skilled in the art.

Pivotally supported upon the shafts 3l8 and not connected thereto, are a pair of levers 3l5 provided at their lower ends with rollers 3IS positioned so that the inclined portions 303 and 308 of the member 308 may bear thereagainst. The levers 3E5 are urged towards each other and into contact with the member 308 by means of the spring 3. The collars upon which the levers 3I5 are mounted are each provided with a pair of cars 3i9 having adjustable screws mounted therein and engaging the opposite sides of a lever 320 secured to, for rotation with, the shaft 3l8. The inner ends of the shafts 3H3 are provided with small eccentric pins 32] which cperate between the forked lower ends 322 of the U-shaped oscillatable arbors 323.

This move- The arbors 323 are pivotally mounted upon the shafts 339 and in turn rotatably support the cutter shafts 324. These shafts are driven from the shafts 339 by means of the pairs of beveled gears 325. The lower ends of the shafts 324 have secured thereto the milling cutters 325 which, as clearly shown in Figure 9, are positioned above the needle anvil 32'! on opposite sides of the needle when inserted. The anvil 321 is adjustabiy mounted upen a support shown in Fig. 9, so as to properly support the needle. A shaft 323, driven in any suitable manner from the power source below the table is provided at its upper end with a spiral driving gear 329 which meshes with a driven spiral gear 330 mounted upon one of the shafts 339 for effecting rotation thereof. This same shaft is provided with a gear 33f which meshes with a similar gear 33! on the other shaft 339. Thus the milling cutters will be caused to revolve from the driven shaft 328. Here again the adjustable stop screw 332 is provided to control the distance which the chuck HG moves the needle N in to the attachment. .The stop screw of course forms no part of this invention where the automatically operating chuck is not disclosed.

In the operation of this device, when the member 338 is positioned as shown in Figure 8, the lower ends of the levers 315 are separated a maximum distance, at which time the milling cutters are closed. When member 308 is at the right, arms 3l5 are closest together and the cutters are separated. The needle is then fed on to the anvil and between the separated cutters. movements the member 308 is moved to the left (Figure 8), so that the inclined portion 308' gradually passes between the rollers on the lower ends of arms 3l5, permitting them to be gradually separated. The result is that the cutters are moved towards each other and into contact with the straight sides of the slot portion of the needle. The needle is being slowly withdrawn at the same time that the member 308 is continuing to move to the left, and traversing the cylindrical portion thereof intermediate the two inclined portions. At the time the saws reach the end of the straight sides of the slot the inclined portion 308 of member 308 has begun to pass between the rollers on the arms 3 I 5. The result is that they begin to slowly move together, gradually bringing the cutters closer together and permitting them to follow the converging edges of the slot down to the dotted position shown in Figure 12. Thus, with the parts properly timed the slot may be properly milled as described. At the end of the milling operation cam 314 causes a quick return of the member 308, swinging the cutters apart, and holding them there until a new needle is inserted between them.

Here again it will be apparent that the attachment may be adapted to follow and mill any desired contour by modifying the shapes of the camming surfaces on the cam 308.

In view of the above description it will be apparent that this invention involves certain principles of construction and arrangement of parts which may be modified by those familiar with the art without material departure from the scope of the real invention involved. I do not, therefore, desire to be strictly limited to the disclosure as given for purposes of illustration, but rather to the scope of the appended claims.

Cam 3% is so shaped that in its first i What I seek to secure by United States Letters Patent is:

1. A milling device as described comprising a housing, a pair of milling cutter supports pivotally mounted in the housing, milling cutters journaled on said supports, means for causing said milling cutters to rotate Qntheir axes, and cam means cooperating with said milling supports for causing the milling cutters to move towards and away from each other in accordance with the cam contour.

2. A milling device as described comprising a housing, a carrier rotatably supported in the housing, means for causing rotation of said carrier about a fixed axis, a pair of rollers pivotally mounted on said carrier, a pair of milling cutters rotatably supported on said rollers, means for causing rotation of said milling cutters as said carrier revolves, and power operated means co-acting with said rollers to cause the milling cutters to move with respect to each other as they revolve about the fixed axis of the carrier and rotate upon their own axes.

3. In a milling attachment of the type described the combination including a carrier journaled for rotation on its axis, a pair of supports pivotally mounted on the carrier, a pair of milling cutters rotatably mounted on the supports, means for rotating the milling cutters actuated by rotation of the carrier, and means cooperating with said pair ,of supports for moving the cutters towards and away from each other while the carrier is revolving.

4. A milling attachment of the type described comprising a housing, a carrier rotatably mounted in the housing, a pair of milling cutters rotatably mounted on the carrier, a gear fixedly supported adjacent the carrier, and gears connected to said milling cutters and meshing with said first mentioned gear for effecting rotation of the cutters-p on their axes as the carrier revolves.

5. A milling attachment of the type described comprising a housing, a carrier rotatably, mounted in the housing, a pair of arms pivotally mounted on the carrier, a pair of milling cutters rotatably journaled on said arms, a ring gear fixed adjacent said carrier, gears meshing with said ring gear and connected to said cutters for rotating them as the carrier revolves, and means for moving said arms towards and away from each other while the carrier revolves.

6. A milling attachment of the type described comprising a support, a pair of arbors pivotally mounted on the support, milling cutters journaled on said arbors, means for effecting rotation of said milling cutters, and means for moving said arbors towards and away from each other including a pair of shafts connected to the arbors, a lever on each of said shafts, resilient means for urging said levers towards each other, and a reciprocal cam movable between said levers to effect oscillation thereof.

ALFRED HOFMANN. 

